You are the watch officer on a power-driven vessel and notice a large sailing vessel approaching from astern. You should __________.

When a power-driven vessel is overtaken by a sailing vessel, the rules of the road indicate that the power-driven vessel is the stand-on vessel. This means that the power-driven vessel should maintain its course and speed, allowing the overtaking vessel to pass safely. The sailing vessel is responsible for keeping clear of the stand-on vessel, as the dynamics of the situation dictate that the faster-moving power-driven vessel should not alter its course abruptly which could cause confusion or an unexpected situation.

Maintaining the course and speed allows the overtaking vessel to anticipate the movement and safely navigate past without unnecessary maneuvering. This is critical for ensuring safety at sea and reducing the risk of collision. The other options, though they might seem plausible, could potentially complicate the situation, as they imply actions that the power-driven vessel should not take while being overtaken.